19 ideas
| 6222 | If a decision is in accord with right reason, everyone can agree with it [Cumberland] |
| Full Idea: No decision can be in accord with right reason unless all can agree on it. | |
| From: Richard Cumberland (De Legibus Naturae [1672], Ch.V.XLVI) | |
| A reaction: Personally I think anyone who disagrees with this should get out of philosophy (and into sociology, fantasy fiction, ironic game-playing, crime…). Of course 'can' agree is not the same as 'will' agree. You must have faith that good reasons are persuasive. |
| 11022 | Gentzen introduced a natural deduction calculus (NK) in 1934 [Gentzen, by Read] |
| Full Idea: Gentzen introduced a natural deduction calculus (NK) in 1934. | |
| From: report of Gerhard Gentzen (works [1938]) by Stephen Read - Thinking About Logic Ch.8 |
| 11065 | The inferential role of a logical constant constitutes its meaning [Gentzen, by Hanna] |
| Full Idea: Gentzen argued that the inferential role of a logical constant constitutes its meaning. | |
| From: report of Gerhard Gentzen (works [1938]) by Robert Hanna - Rationality and Logic 5.3 | |
| A reaction: Possibly inspired by Wittgenstein's theory of meaning as use? This idea was the target of Prior's famous connective 'tonk', which has the role of implying anything you like, proving sentences which are not logical consequences. |
| 11023 | The logical connectives are 'defined' by their introduction rules [Gentzen] |
| Full Idea: The introduction rules represent, as it were, the 'definitions' of the symbols concerned, and the elimination rules are no more, in the final analysis, than the consequences of these definitions. | |
| From: Gerhard Gentzen (works [1938]), quoted by Stephen Read - Thinking About Logic Ch.8 | |
| A reaction: If an introduction-rule (or a truth table) were taken as fixed and beyond dispute, then it would have the status of a definition, since there would be nothing else to appeal to. So is there anything else to appeal to here? |
| 11213 | Each logical symbol has an 'introduction' rule to define it, and hence an 'elimination' rule [Gentzen] |
| Full Idea: To every logical symbol there belongs precisely one inference figure which 'introduces' the symbol ..and one which 'eliminates' it. The introductions represent the 'definitions' of the symbols concerned, and eliminations are consequences of these. | |
| From: Gerhard Gentzen (works [1938], II.5.13), quoted by Ian Rumfitt - "Yes" and "No" III | |
| A reaction: [1935 paper] This passage is famous, in laying down the basics of natural deduction systems of logic (ones using only rules, and avoiding axioms). Rumfitt questions whether Gentzen's account gives the sense of the connectives. |
| 13832 | Natural deduction shows the heart of reasoning (and sequent calculus is just a tool) [Gentzen, by Hacking] |
| Full Idea: Gentzen thought that his natural deduction gets at the heart of logical reasoning, and used the sequent calculus only as a convenient tool for proving his chief results. | |
| From: report of Gerhard Gentzen (Investigations into Logical Deduction [1935]) by Ian Hacking - What is Logic? §05 |
| 10067 | Gentzen proved the consistency of arithmetic from assumptions beyond arithmetic [Gentzen, by Musgrave] |
| Full Idea: Gentzen proved the consistency of arithmetic from assumptions which transcend arithmetic. | |
| From: report of Gerhard Gentzen (works [1938]) by Alan Musgrave - Logicism Revisited §5 | |
| A reaction: This does not contradict Gödel's famous result, but reinforces it. The interesting question is what assumptions Gentzen felt he had to make. |
| 17488 | Empiricist theories are sets of laws, which give explanations and reductions [Glennan] |
| Full Idea: In the empiricist tradition theories were understood to be deductive closures of sets of laws, explanations were understood as arguments from covering laws, and reduction was understood as a deductive relationship between laws of different theories. | |
| From: Stuart Glennan (Mechanisms [2008], 'Intro') | |
| A reaction: A lovely crisp summary of the whole tradition of philosophy of science from Comte through to Hempel. Mechanism and essentialism are the new players in the game. |
| 17493 | Modern mechanism need parts with spatial, temporal and function facts, and diagrams [Glennan] |
| Full Idea: Modern champions of mechanisms say models should identify both the parts and their spatial, temporal and functional organisation, ...and the practical importance of diagrams in addition to or in place of linguistic representations of mechanisms. | |
| From: Stuart Glennan (Mechanisms [2008], 'Discover') | |
| A reaction: Apparently chemists obtain much more refined models by using mathematics than they did by diagrams or 3D models (let alone verbal descriptions). For that reason, I'm thinking that 'model' might be a better term than 'mechanism'. |
| 17487 | Mechanistic philosophy of science is an alternative to the empiricist law-based tradition [Glennan] |
| Full Idea: To a significant degree, a mechanistic philosophy of science can be seen as an alternative to an earlier logical empiricist tradition in philosophy of science that gave pride of place to laws of nature. | |
| From: Stuart Glennan (Mechanisms [2008], 'Intro') | |
| A reaction: Lovely! Someone who actually spells out what's going on here. Most philosophers are far too coy about explaining what their real game is. Mechanism is fine in chemistry and biology. How about in 'mathematical' physics, or sociology? |
| 17489 | Mechanisms are either systems of parts or sequences of activities [Glennan] |
| Full Idea: There are two sorts of mechanisms: systems consist of collections of parts that interact to produce some behaviour, and processes are sequences of activities which produce some outcome. | |
| From: Stuart Glennan (Mechanisms [2008], 'Intro') | |
| A reaction: [compressed] The second one is important because it is more generic, and under that account all kinds the features of the world that need to be explained can be subsumed. E.g. hyperinflation in an economy is a 'mechanism'. |
| 17490 | 17th century mechanists explained everything by the kinetic physical fundamentals [Glennan] |
| Full Idea: 17th century mechanists said that interactions governed by chemical, electrical or gravitational forces would have to be explicable in terms of the operation of some atomistic (or corpuscular) kinetic mechanism. | |
| From: Stuart Glennan (Mechanisms [2008], 'Intro') | |
| A reaction: Glennan says science has rejected this, so modern mechanists do not reduce mechanisms to anything in particular. |
| 17491 | Unlike the lawlike approach, mechanistic explanation can allow for exceptions [Glennan] |
| Full Idea: One of the advantages of the move from nomological to mechanistic modes of explanation is that the latter allows for explanations involving exception-ridden generalizations. | |
| From: Stuart Glennan (Mechanisms [2008], 'regular') | |
| A reaction: The lawlike approach has endless problems with 'ceteris paribus' ('all things being equal') laws, where specifying all the other 'things' seems a bit tricky. |
| 6217 | Natural law is supplied to the human mind by reality and human nature [Cumberland] |
| Full Idea: Some truths of natural law, concerning guides to moral good and evil, and duties not laid down by civil law and government, are necessarily supplied ot the human mind by the nature of things and of men. | |
| From: Richard Cumberland (De Legibus Naturae [1672], Ch.I.I) | |
| A reaction: I agree that some moral truths have the power of self-evidence. If you say they are built into the mind, we now ask what did the building, and evolution is the only answer, and hence we distance ourselves from the truths, seeing them as strategies. |
| 6221 | If there are different ultimate goods, there will be conflicting good actions, which is impossible [Cumberland] |
| Full Idea: If there be posited different ultimate ends, whose causes are opposed to each other, then there will be truly good actions likewise opposed to each other, which is impossible. | |
| From: Richard Cumberland (De Legibus Naturae [1672], Ch.V.XVI) | |
| A reaction: A very interesting argument for there being one good rather than many, and an argument which I don't recall in any surviving Greek text. A response might be to distinguish between what is 'right' and what is 'good'. See David Ross. |
| 6218 | The happiness of individuals is linked to the happiness of everyone (which is individuals taken together) [Cumberland] |
| Full Idea: The happiness of each person cannot be separated from the happiness of all, because the whole is no different from the parts taken together. | |
| From: Richard Cumberland (De Legibus Naturae [1672], Ch.I.VI) | |
| A reaction: Sounds suspiciously like the fallacy of composition (Idea 6219). An objection to utilitarianism is its assumption that a group of people have a 'total happiness' that is different from their individual states. Still, Cumberland is on to utilitarianism. |
| 6220 | The happiness of all contains the happiness of each, and promotes it [Cumberland] |
| Full Idea: The common happiness of all contains the greatest happiness for each, and most effectively promotes it. …There is no path leading anyone to his own happiness, other than the path which leads all to the common happiness. | |
| From: Richard Cumberland (De Legibus Naturae [1672], Ch.I.VI) | |
| A reaction: I take this as a revolutionary idea, which leads to utilitarianism. It is doing what seemed to the Greeks unthinkable, which is combining hedonism with altruism. There is no proof for it, but it is a wonderful clarion call for building a civil society. |
| 6216 | Natural law is immutable truth giving moral truths and duties independent of society [Cumberland] |
| Full Idea: Natural law is certain propositions of immutable truth, which guide voluntary actions about the choice of good and avoidance of evil, and which impose an obligation to act, even without regard to civil laws, and ignoring compacts of governments. | |
| From: Richard Cumberland (De Legibus Naturae [1672], Ch.I.I) | |
| A reaction: Not a popular view, but I am sympathetic. If you are in a foreign country and find a person lying in pain, there is a terrible moral deficiency in anyone who just ignores such a thing. No legislation can take away a person's right of self-defence. |
| 17494 | Since causal events are related by mechanisms, causation can be analysed in that way [Glennan] |
| Full Idea: Causation can be analyzed in terms of mechanisms because (except for fundamental causal interactions) causally related events will be connected by intervening mechanisms. | |
| From: Stuart Glennan (Mechanisms [2008], 'causation') | |
| A reaction: This won't give us the metaphysics of causation (which concerns the fundamentals), but this strikes me as a very coherent and interesting proposal. He mentions electron interaction as non-mechanistic causation. |